Depends on with whom you are running if it's pub zerg then I don't know I don't pub but for organized group play there is pretty much only one viable build with some minor alterationshttp://gw2skills.net...vHimJP1yAwsAA-w

Want to get your input as I am currently 38 on fotm and will soon head into the 40 range. With the 2 other guild members (a warrior & thief) I run with I honestly don't see myself going beyond 48 since I got that lovely grind I need to do for laurels and/or guild missions for the accessories. Enjoyed the thread and made some changes to my current gear makeup and while the stat changes are minor (improves from my previous setup) should I look into more offensive dps considering I'll enter the 40+ fotm? I mostly use GS as that is my favorite weapon and switch my secondary weapon depending on the situation. Also like most guardians my "Save Yourself" slot I usually switch up with wall, shield, or retreat considering what fractal I am currently on while naturally switch the corresponding Virtues trait in the 1st tier. Read in some threads that in 40+ too much survival might not help but any words of wisdom would be great.

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My goal as a Mesmer is to be effective in organized strike teams of 10-15 people as well as 1v1-3 roaming situations in WvW (guerrilla warfare). I am going for a “good offense is the best defense” kind of build with survivability based on “skill” in constant movement and deception through clones. I am focusing on killing my opponent before they can kill me, and don’t often find myself in the heat of battle. I enjoy using my Phantasmal Berserker(Greatsword 4 Skill) in the hectic cluster of battle as well as an immediate shatter after throwing Mirror Blade(Greatsword 2 Skill) into a mob to apply damage(Mind Wrack) or confusion(Cry of Frustration) to a group. Meanwhile I use Spatial Surge(Greatsword 1 Skill) on targeted foes that could be in or out of the heat of battle. I also find myself using my sword and pistol to pick off and burst down enemies outside the heat of battle (ex. Staff Elementalists).

I'm sorry to disappoint you but you can't be good in 15 ppl group and as roumer with the same build
those are very VERY different games

In group play you want to be pretty much as defensive as possible to not play the famous revive bot . Unfortunatelly phantasms survivability is like 1 second thx to all the AoE flying around. SO with all this in mind mesmers in group play are pretty much "Walking Veil". Don't get me wrong those Null Fields, Feadbacks and Portals are awesome but don't expect to kill anything. And if you go with offensive build expect everyone hating you for reviving enemy because all your deception and defense via clones is useless in mass pvp.
Also u want focus not pistol as your offhand

Roaming on the other side is completely different, here you want to go with any 1v1 good spvp build speced for killing ...

The point of my post---and the discussion of the Grenade Kit versus the Flamethrower---is that there are many classes beyond Warrior, Mesmer, and Guardian that fulfill roles that those classes can't. The Engineer has arguably the best group PvE healing skill in the game providing two Water fields between the overcharge and toolbelt and, to be honest, completely overpowered condition removal.

This allows classes like the Warrior to instead focus entirely on offense, where one might otherwise be driven to slot "Shake It Off!" It also allows Guardians to drop Pure of Voice and Soldier runes, focusing instead on offering more unique buffs and control than slotting 3 shouts on their bar.

The fact of the matter is: this game is about 5-player parties, not 3-player parties. And if people would allow themselves to think outside the box more often they'd come to realize that the 3-class meta of Warrior, Mesmer, and Guardian, while one way of doing things, is not always the best or most efficient method.

Engies may have "the best group PvE healing skill in the game" but it's not needed
Engies may have "completely overpowered condition removal" but it's not needed
Warriors don't take Shake it Off! even without Engie in party
Guardians take whatever they need even without Engie in party

So what exactly is your point? Engie is awesome in something that no one needs? Good for you
W/M/G meta may not be the best but no one prooved otherwise yet (and trust me they tried)